A printed circuit board (PCB) may provide mechanical support for an electronic circuit that includes components mounted to the PCB. The PCB may include traces to electrically connect structures on the PCB and/or components mounted on the PCB. The PCB may include one or more layers, where a trace on one layer may be electrically connected to a trace on another layer or to the other layer through an electrical connection called a “via.”
Traces on a PCB may be organized as differential pairs. An electrical signal may travel through each trace of a differential pair of traces, where the two electrical signals may define a differential signal. In some examples, a differential clock signal or a data signal may travel through a differential pair of traces. The traces of an edge-coupled differential pair may be positioned substantially parallel to each other on a layer of a PCB. The traces of a broadside-coupled differential pair may be positioned substantially parallel to each other on two different layers of a PCB.
The flow of electrical signals through a trace or a via on a PCB may create electromagnetic waves that may affect the flow of electrical signals through other traces or vias in the PCB. The electromagnetic waves may be referred to as noise, interference, or crosstalk. The trace or via creating the electromagnetic waves may be referred to as the aggressor trace or aggressor via. The trace(s) or via(s) affected by the electromagnetic waves may be referred to as the victim(s).
In an electronic device, a PCB may include two or more differential pairs of traces, where each trace is positioned substantially parallel to the other traces. Each trace may operate as an aggressor with respect to other traces because the electrical signals in each respective trace may generate electromagnetic fields and waves that affect the transmission of electrical signals through other traces and other vias. Thus, each trace may be a victim and/or an aggressor, depending on which trace is being analyzed.